<!doctype html>
<html>
<head>
	<meta charset="utf-8">
	<link rel="stylesheet" type="text/css" href="css/index.css">
</head>
<body>
<form action="#" method="GET" class="form">
	<label>用户名</label><input type="text" value=""/>
	<span>请输入正确的用户名</span>
</form>
</body>
</html>